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January 2018

Longest Streaks of High Temperatures of 32 Degrees or Colder



Since the winter of 1940 there have been ten streaks of ten days or longer with high temperatures that were 32° or colder (streaks of this length occur, on average, once every eight years).  The most recent, a streak of fourteen days, occurred in the winter of 2017-18 (Dec. 26 thru Jan. 8).  It was the third longest on record, behind a sixteen-day streak in the winter of 1961, and a fifteen-day streak in the winter of 1881.  This winter's streak closely mirrored one during the winter of 2001 that also started in December and ended in January.  (However, it's temperatures weren't as cold and was one day shorter.)  What follows are some other interesting observations about New York's longest cold streaks (nine days or longer):


  • As mentioned above, the longest streak came in the winter of 1961 when the City shivered through sixteen days in a row of sub-freezing highs from Jan. 19 thru Feb. 3.  The "warmest" temperature during this time frame was 29°.  It would be seventeen years before another streak of ten days or longer occurred.
  • No winter has had two of these lengthy streaks, but 1958 had one in February of twelve days and a ten-day streak in December.  Additionally, there have been numerous winters with two or more smaller streaks of four, five or six days.
  • The earliest of the streaks occurred at the beginning of the winter of 1957-58 when there was a ten-day streak from Dec. 7 to 16.  The latest streaks were in February 1958 (Feb. 8-19) and February 1979 (Feb. 9-19).  What was remarkable about the 1979 streak was the fact that, not only was it late in the winter, but it had the most days with lows in the single digits - eight.  It followed closely behind a nine-day streak in January 1968 as the coldest of the cold waves; Feb. 1979, however, had the coldest average high (20.5) while Jan. 1968 had the coldest average low (6.4).
  • There were extended streaks in the consecutive winters of 1977, 1978 and 1979 (and there was one in 1981).  1977's streak was book-ended by smaller streaks of five days before (broken up a day with a high of 41°) and four days after (broken up by a day with a high of 36°).  In total, 18 of the 20 days between Jan. 5-24 saw highs at freezing or below.  There was also another cluster of winters with lengthy cold waves, during the winters of 2001, 2003, 2004 and 2005.
  • Thirteen of the seventeen streaks of nine days or longer saw some mornings with lows in the single digits or colder (three had sub-zero readings).
  • Three of the streaks of nine days or longer had snowstorms of 12 inches or more. 1961's cold wave nearly had two snowstorms but two-thirds of the 17.4" accumulation from the snowstorm on Feb. 3-4 fell on the day when the 16-day streak ended as the high reached 34°.  


Chart - snowstorms during cold waves


  • The 13-day steak during the winter of 2000-01 had the highest mean temperature. 


 Chart - Longest Cold Streaks in NYC


Second Warmest Year Globally Is New York's Fourteenth Warmest

Polar bear on melting iceFollowing what was the warmest year on record worldwide, 2017 checked in as the second warmest.  In New York, however, the year didn't rank quite as high, coming in as fourteenth warmest.  But make no mistake, it was still a warm year, ranking higher than 135 others (New York's weather records go back to 1869, which is much further than most US cities).  The fact that the year had five months with below average temperatures makes its ranking rather impressive.  These five months were balanced by the warmest February and October on record.  Nine of the City's fifteen warmest years have now occurred in this century (including the past three years). 


 Chart - new york's 15 warmest years






Comparing New York's Three Biggest Snowstorms

Blizzard of 2016


New York's three biggest snowstorms each buried the City under more than two feet of snow (four others have produced between 20"and 21").  They occurred in different months of the winter: the biggest, totaling 27.5", was in January 2016; the second greatest, 26.9", buried New York in February 2006, and the third deepest, 26.4", was the day after Christmas in December 1947.  And the bulk of these storms' snow fell on different days of the week: Friday (1947), Saturday (2016), and Sunday (2006).  The amounts of each storm were approximately what falls during an entire winter.


Although it's fallen to third place, what makes the 1947 snowstorm stand out from the other two is that it occurred during a cold and very snowy winter while the others accounted for much of the snow during their mild winters.  The 2006 snowstorm accounted for all but 13.1" of the snowfall that winter while 2016's blizzard accounted for all but 4.6".  By contrast, the winter of 1947-48, which at the time was snowiest on record (now ranked second behind the winter of 1996), had 37.4" of snow on top of December's enormous accumulation.  Each month of that winter had temperatures well below average, especially December.  By contrast, the winter of 2006 had the fourth mildest January on record while the winter of 2016 was the second mildest on record, largely due to the mildest December on record.




Interestingly, before being crowned the biggest snowstorm in NYC history, 2016's snowstorm was ranked second, with 0.1" less than 2006's amount.  Then three months later the National Weather Service announced that it had re-evaluated the measurement at Central Park's weather station and added 0.7" to the originally reported amount, making it top dog.  (The winter before that the NWS adjusted three snowfalls, adding 3.1" to that winter's snowfall total.) 


Although it's now ranked third, the snowstorm of Dec. 26-27, 1947 may have been the most debilitating of the three storms.  First, the snow of that storm had a higher water content than the others, especially 2006's.  1947's snowfall was equivalent to 2.40" liquid compared to 2.32" for 2016's blizzard and 1.86" for the fluffy snow of 2006.  Second, the days following the 1947 storm were much colder than those after the other two storms, so snow melt was minimal.  Temperatures during the five days after the 1947 storm were seven degrees colder than average, with high temperatures ranging from 28° and 35°.  By comparison, temperatures after the 2006 and 2016 storms were six and four degrees above average, respectively.  In 2006 three of the five days after the Feb. 11-12 blizzard saw highs in the mid-to upper 50s.  In 2016 the third and fourth days after the storm never saw the temperature drop to freezing or colder.  Add to these reasons the fact that snow removal techniques of 70 years ago were primitive compared to those of the 21st century, and a strong argument can be made that the 1947 snowstorm was the worst of the three. 



 NYCs Three Biggest Snowstorms

 Snowstorm fun facts



Greatest Hits of New York Weather in 2017



Although two months in 2017, February and October, became the warmest on record, the year may be best remembered for the Arctic outbreak that moved in on Christmas Day and stayed locked in place through the first week 2018.  It produced the year's coldest reading, 9°, which was reached minutes before the year ended.  Other highlights?  At the other end of the thermometer, the year's hottest temperature, 94°, occurred on June 13 and again on July 20.  In terms of precipitation, the biggest snowfall was 9.4" on Feb. 9; the biggest rainstorm was 3.03" on Oct. 29.  Finally, although 2017 was the fifth year of the past six to have below average precipitation, it was the fifth in a row with above average snowfall.  What follows are additional highlights of the year, arranged in chronological order.



A record high of 66° came five days after a snowfall of 5.1" and three days after the coldest day of the winter (high/low of 23/14).  This was the warmest reading in January in 10 years.  (And on Feb. 24 a high of 70° was the earliest date in ten years for the first 70-degree reading.)


66 degrees



The biggest snowfall of the winter, 9.4", buried the City less than 24 hours after the temperature topped out at 62°.  This snowfall was even more impressive considering that this would be the mildest February on record.


Snowstorm of feb 9 2017



An intense late-winter storm dumped 7.6" of snow and sleet on the City but was considered a "flop" since it was expected to dump between 14" and 20".  After starting as heavy snow in the pre-dawn hours the precipitation changed to sleet when the storm moved closer to the coast than expected.  This nor'easter came in the midst of a six-day period (March 11-16) that had temperatures that were 15 degrees below average (average high/low of 32/20).



The high on Easter Sunday reached 87°, the second warmest reading on record for this holiday.




MAY 17-19

An early three-day heat wave (with highs of 90°, 92° and 91°) was followed by six days with highs that never got out of the 60s.  This heat wave was the first in May of three days or more since 2001. 



After one of the coolest beginnings to September on record, the next eight weeks were seven degrees warmer than average, including the mildest October on record.  This included the latest 90-degree reading since 1970 (91° on Sept. 24) and the latest date on record for a low in the 70s, on Oct. 9.  Half of the days in the six-week period between Sept. 21 and Nov. 3 were ten degrees or more warmer than average.



On the five-year anniversary of superstorm Sandy, the biggest rainstorm of the year produced 3.03", besting the deluge of May 5 by 0.01" (the rain on 5/5 poured down in just three hours).  The biggest rainstorm in three-and-a-half years, it produced more rain than four of the months in 2017.





A record low of 25°, reported shortly before midnight, was the earliest date for a reading this cold since 1976.  In addition to this record, another was set the next day, making this the first occurrence of back-to-back record lows since August 1994. 



The year ended on a teeth-chattering note with six days in a row having highs of 28° or colder, which included the coldest mean temperature in two years (high/low of 18/11 on Dec. 28).  Then shortly before midnight on New Year's Eve the temperature dropped to 9°, making it not only the coldest reading of the year, but the second coldest reading to occur during the Times Square ball-drop.  This cold streak would continue through Jan. 8, making it the third longest streak on record (two days shorter than a 16-day streak in the winter of 1961 and one day shorter than a streak in the winter of 1881).








December Weather Recap - 2017 Ends With Harsh Cold Wave

Frigid new years eve in times squareAlthough 2017 featured two months, February and October, that were the warmest on record, the year may be best remembered for December's Arctic outbreak that moved in on Christmas Day and stayed locked in place through the first week of 2018.  On Dec. 28 the high/low of 18/11 made it the coldest day of the year (based on mean temperature), followed on Dec. 31 by the coldest temperature of the year, when the mercury fell to shortly before the ball-drop in Times Square.  The last five days of the month had highs of 25° or colder, the first streak of this length since January 2004.  Here are some other observations:


  • The first six days of December were six degrees above average while the final six days were 15 degrees below average.  Overall the month was 2.5 degrees colder than average and was the coldest December in seven years (and the third coldest in 20 years).  Until the Arctic front moved through on Christmas Day the month had close to average temperatures.
  • For the first time since 2002 December was the coldest month of the year, just the 15th time since 1900 that this has happened.  
  • The month had 2.21" of precipitation, joining three other months in 2017 with less than 2.50" of precipitation.  This was the driest December since 2006 (when 2.15" was measured).  The biggest rainfall, 0.75", was on Dec. 5, pouring down that night.  This was also the mildest day of the month, with a high/low of 61/50.
  • Measurable snow fell on four days, totaling 7.7".  The first snowfall, on Dec. 9, was the biggest, with 4.6" measured.
  • In addition to the Arctic outbreak at the end of the month, there was a cold snap mid-month that had three days in a row with highs of 32° or colder (Dec. 13-15).  During this outbreak there were two 1.2" snowfalls on consecutive days (Dec. 14 and 15).
  • The month's nine days with highs of 32° or colder was the most in December since 2000 (which, like this December, ended with an extended Arctic outbreak, the second longest on record, that lasted 13 days, from Dec. 22 to Jan. 3).
  • The six-day streak with highs of 32° or colder is behind eight streaks in December of seven days or longer.


December Cold Streaks

  • Finally, the high of 18° on Dec. 28 was just the fifth time since 1960 that there was a high in the teens in December.


Coldest december high temps

Here are other December recaps:

December 2016

December 2015